Synthesis of a branched star copolymer by aqueous SET-LRP and its thermo-stimuli response. Issue 4 (2nd April 2020)

• Record Type: Journal Article
• Authors: Wang, Ling; Ding, Wei; Song, Kaoping; Dong, Chi; Chen, Meixin; Zhou, Huajian
• Is Part Of: Journal of macromolecular science. Volume 57:Issue 4(2020)
• Page Start: 266
• Page End: 273
• Publication Date: 2020-04-02
• Subjects: Single-electron transfer living radical polymerization -- macromonomer -- acrylamide -- copolymerization -- thermo-stimuli response; Polymers -- Periodicals; Polymerization -- Periodicals; 547.7
• DOI: 10.1080/10601325.2019.1691452
• Languages: English
• ISSNs: 1060-1325

Abstract

Abstract: Thermally responsive star-shaped polyacrylamides have been efficiently synthesized by copolymerization of acrylamide (AM) with AM-based macromonomer (MPAD) by single-electron-transfer living radical polymerization. Copolymerizations using Gly-Br3 as an initiator were catalyzed by full in situ disproportionation of CuBr/Me6 TREN to Cu(0) powder and CuBr2 and were performed in H2 O at 25 °C. The polymerization proceeded smoothly, and the time dependence of ln([ M ]0 /[ M ]) was linear, implying that the copolymerization was a living polymerization. The polymer products were characterized by FTIR spectroscopy, 1 H NMR spectrometry, and atomic force microscopy. The responsiveness of the water-soluble star-shaped copolymers were studied by turbidity measurements, dynamic light scattering, and transmission electron microscopy. The lower critical solution temperature of a random copolymer can be tuned by changing the feed ratio of MPAD in its synthesis. The phase transition temperature of the copolymer decreased with increasing MPAD content. At a feed ratio of MPAD of 10%, the copolymer obtained exhibited a strong thermal response and could form vesicles. Graphical Abstract: